288 NATURAL SCIENCE [October 



the general circulation in the show tanks, and is never returned to the laboratory 

 tanks after it has passed through them. Experience shows that the theory of 

 'circulation,' as applied to aquaria, is illusory and in jiractice disastrous. 



Science announces that the Zoological Expedition sent by Columbia Uni- 

 versity this summer to Alaska have lost all the results of their season's work by 

 the wreck of the City of Mexico, in which they were returning. Fortunately 

 all the members of the party were landed in safety. The Duke of the Abruzzi and 

 his companions successfully ascended Mount St Elias on July 30, 31. The height 

 of the mountain was ascertained to be 18,100 ft. Dr Sella was of the party and 

 we may hope for excellent photographs as illustration to the report of the 

 expedition. 



We are indebted to Mr Duerden for an interesting account of this summer's 

 work of Prof. W. K. Brooks' party of Baltimore students in studying the tropical 

 life of Jamaica. As we have previously announced, the party this year was 

 under the direction of Prof. J. E. Humphrey, and established a temporary 

 laboratory in an hotel at Port Antonio, a locality in many respects more advan- 

 tageous than Port Henderson, the former headquarters. The director, one of 

 the most distinguished of the younger American botanists, collected and preserved 

 a large amount of botanical material, giving special attention to the shell-perfor- 

 ating algae and to the embryology of certain flowering plants. We deeply regret 

 to add that towards the end of the course of study he became ill and died almost 

 immediately. Another botanist, Mr A. Fredholm, dried a large collection of 

 Jamaica plants for the herbarium of the U.S. National Museum. Dr F. S. 

 Conant continued his researches on the medusae, begun last year. The chief 

 object of his investigation this season was the function of the sensory organs of 

 the medusa, and material was prepared with especial reference to a study of the 

 changes, under the influence of light and darkness, in the pigment of the retina 

 of the eyes. Dr H. L. Clark also continued his previous researches on the 

 echinoderms. He devoted special attention to the life-history of the interesting 

 holothurian Chirodota. Mr Sudler returned to Port Henderson to dredge for the 

 small crustacean Lucifer, which he could not find at Port Antonio. Mr Grave 

 studied various ophiurans, and doubled the number of species recorded from 

 Jamaica. The eggs of one species were artificially fertilised in the laboratory, and 

 a complete series of the embryos from the single cell to the fifteen-day Pluteus 

 stage was satisfactorily preserved for future examination. Mr E. N. Berger 

 devoted his time chiefly to insects and arachnids, obtaining many embryonic 

 stages, especially of a pseudoscorpion, probably Obisium. There were also j unior 

 students. Mr Duerden, as Curator of the Jamaica Institute, was invited to 

 join the party ; he profited by the occasion in enriching the Museum collection, 

 and in continuing his researches on the corals. 



ERRATA 

 Page 88, lino 3. For ' invariable ' read ' variable.' 

 „ 148, ,, 6. „ 'Marlotf „ 'Marlatt.' 

 ,, l. r >8, ,,12. ,, 'collection' ,, 'collector.' 



